Puya chilensis, or Puya coarctata locally known as Chagall, originates from the arid hillsides of Chile. Puya is a genus also found on the mountains and foothills of the Andes.
These evergreen perennial are terrestrials bromeliads, with strong root systems buried in the earth. The basic form is a large rosette of slender, pale green, leaves spines, pointing inward as well as outward, blade-like, which make for a plant both striking and graceful. Over the years they form extensive clumps, spreading along the contours of the land, the rosettes standing up to 2m high. Each spring the clumps of puyas send up great spikes, 2-3m high, atop which cluster the flowers.
The actual flower head is about 1m long and packed with racemes of chunky flowers, the sterile tips of which sticks out, affording a perch for thirsty birds. The individual waxy blooms are 6-8cms long, providing a deep receptacle for the nectar that the birds, bees and even some gardeners find so compelling. The individual Puya flower is a thing of beauty and wonder. They are a strident green-yellow, bright without being lurid, as if lit from within.
There is a sinister aspect to the Puya: the margins of the leaves are edged with fiendish, hooked thorns. These are bad news for the weeding gardener and to the birds. Plants should be handled with great care. Thick protective clothing is recommended. Always plant away from path edges and areas where children are likely to play. Over time Puya chilensis can colonize large areas.
Hardiness zone: 9 -11, (-5°C/25°F, 4°C/40°F) in winter. If grown outside it is able to withstand light frosts and may even survive brief overnight temperatures as low as -5 C. In colder regions it needs some winter protection and is best either grown or brought inside during winter. They will bloom the soonest if protected from frost. During the summer, it's best to give them some mid-day shade if it gets into the upper 90s or above. It will tolerate some shade but is best grown in full sun.
Water moderately whenever the soil is about 2/3 dry down where the roots are. Avoid letting the soil completely dry out, but don't let it stay soggy either. Never let the pots sit in a tray of water. Also keep them fairly dry during the winter, unless temperatures are above freezing. Feed once a month during periods of active growth, using an ordinary complete vegetable fertilizer at 1/3 the recommended dose.